Meeke R, Wren W, Davenport J, O'Griofa P
Acta Anaesthesiol Scand. 1984 Dec;28(6):696-9. doi: 10.1111/j.1399-6576.1984.tb02147.x.
The accuracy of tidal volume measurements made with a Wright Haloscale infant respirometer in children breathing spontaneously during general anaesthesia was assessed by a bench test. The tidal volumes and peak flow rates of 20 spontaneously breathing, anaesthetised children were measured with a pneumotachograph before and during surgery, and similar volumes, at the same flow rates, were delivered by a calibrated syringe simultaneously to the respirometer and a pneumotachograph. The results reveal that the mean (+/- s.d.) peak gas flow rates of children aged 6 years and less, 7.5 (+/- 1.6) and 9.3 (+/- 0.1) l/min before surgery and during surgery respectively, are significantly less than the peak flow rates, 11.3 (+/- 1.0) and 11.9 (+/- 1.5) before and during surgery, respectively, of children aged more than 6 years; and that the respirometer underestimates tidal volume by 10% when the peak flow rate is 11 l/min, and the percentage error in tidal volume estimation by the respirometer increases as the peak gas flow declines below 10 l/min.
通过一项台架试验评估了在全身麻醉期间自主呼吸的儿童中使用赖特半量程婴儿呼吸计测量潮气量的准确性。在手术前和手术期间，用呼吸流速计测量了20名自主呼吸的麻醉儿童的潮气量和峰值流速，同时通过校准注射器以相同流速向呼吸计和呼吸流速计输送相似体积的气体。结果显示，6岁及以下儿童在手术前和手术期间的平均（±标准差）峰值气流速度分别为7.5（±1.6）和9.3（±0.1）升/分钟，显著低于6岁以上儿童在手术前和手术期间分别为11.3（±1.0）和11.9（±1.5）的峰值流速；当峰值流速为11升/分钟时，呼吸计低估潮气量10%，并且随着峰值气流速度降至10升/分钟以下，呼吸计估计潮气量的百分比误差会增加。
